Some progressive processing methods are provided with a feeding step and a pressing step. The feeding step carries strip-shaped sheets to a press machine and the pressing step presses the strip-shaped sheet.
Japanese Patent Publication No. H11-300418 discloses welding an end of a strip-shaped sheet located in the direction opposite the direction in which the strip-shaped sheet is fed with an end of a new strip-shape located in the direction in which the new strip-shaped sheet is fed and feeding the new strip-shaped sheet to the press machine subsequent to the strip-shaped sheet. The above described welding is suited for processing thick strip-shaped sheets. Thus, application of the above described welding to thin strip-shaped sheets results in reduced tensile strength, straining, etc. to exhibit unstable welding quality and therefore is problematic in terms of ensuring strength of the strip-shaped sheets being fed.